Screw and trunnion nut device and method of making it



May 28, 1935. -J J. M LAUGHLIN 2,002,671

SCREW AND TRUNNION NUT DEVICE AND METHOD OF MAKING IT Filed Feb. 21, 1935 ATTORNEY Patented May 2a, 1935 s 2,002,671

UN JSTATESAPATENT. OFFICE scnnw m TRUNNION NUT DEVICE AND METHOD OF MAKING rr 3 John J. McLaughlin, North Tonawanda, Y., .assignor to Buffalo Bolt Company, North Tonawanda, N. Y., a corporation of New York Application February 21, 1935, Serial No. 7,509

14 Claims. (01. 10-86) My present invention results from my pracunder a knife which severs theblanks which are tical experience with hose clamps of the type then completed by tapping threads in the preshown in Patent 1,815,145, granted July 21, 1931, formed hole therefor. and particularly from myexperience in connec- Thus all the stock is used except the slug 5 tion with large quantity production of 'trunpunched from the center, and the automatic 5 nioned nuts therefor. As shown in the patent, flattening pu c a d Cut-Off completes the 111117 the clamp is of a type having an upstanding bearready for screw tapping. The resulting nut has ing in. which the head of the clamping screw special novelty and advantages where it is used is swivelled, and in which the hose engaging body as a trunnion nut in combination with the wire of the clamp consists of more 0151685 parallel loop bearings shown in said patent. wires which are bent circularly to lit the hose, The above and other features of my invention and at a point adjacent the nut end of the may be more fully understood from the followclamping screw, are provided with means for ening description in connection with the accomgaging opposite aligned projections on a clamppanying drawing, in which ing nut threaded on the clamping screw. Fig. 1 is a view, transversely of the hm pipe,

While my invention centers on a nut having showing a hose clamp in sideelevation; opposite aligned projections for applying tension Fig. 2 is a side elevation of the hose, affordor thrust of a screw, its novel features have-"ing a view of the clamp viewed from the nut special significance in connection with projecend of the clamping screw,"

1 2o tion-engaging wire loops that resemble those Figs. 3, 4 and 5 are respectively face edge and go shown in said patent. In said patent the wires longitudinal sectional views of my improved nut are similarly and symmetrically bent helically clamp, on a much larger scale than that of Fig.

outward and toward one another to form apair 2, the section shown in Fig. 5 being on the line a of single-turn loop bearings for the nut"pro 5-5, Fig. 3; i

Jections, and the projections are trunnions, the Fig. 6 is a vertical sectionthrough the operg5 ends of which have annular flanges intended to ating parts of the die punch and cut-oft, with hold the loops from slipping o the stock in' place therein;

These flanges are unsatisfactory for that Fig. 7. is a face view of the lower stationary purpose, and also as concerns cheap quantity member of the press.

production, becaue it has been found imprac-- In the illustrative form shown inFigs. 1 and 2, 0

tical to merely upset the ends of the trunnions the body of the clamp is somewhat like that to form flanges of the desired depth, or to form shown in said patent. It is preferably formed them by turning the trunnions in a lathe. So from a single length of stout and stiff wire of in practice, they were made-by stamping cylinconsiderably resiliency. This wire is doubled drical stock to flatten the central thread portion, and bent to form a short helix l0 preferably 35 and to stamp circular portions for the upper having one and one-half convolutions. The wire and lower halves of the flanged trunnions. The ends extend from this helix in generally parallel latter operation presses out flashes along the relation and are curved in a. direction at right trunnions; and the practice was to drilland tap angles to the helix to form spaced rings II the I o the central portion and finally remove the ends I! of which lie between the bodies of the flashes in a trimming press. a rings adjacent the helix i0. Adjacent the ends As contrasted with this, my invention conthe wires are each bent in a single convolution templates taking cylindrical stock of approxito form a pair of axially aligned bearings l3. mately the diameter desired for the trunnions A nut is provided between the bearings I 3, and and. run it through a reciprocating press me.- it has oppositely extending projections carried 45 chine wherein a single pair of dies depress and in said bearings, each projection including a thereby expand the central nut portion between rounded, trunnion-like portion l5, it, formed the trunnions, and also flatten the ends beyond so as to secure the projections in the bearings the trunnions so that the edges diverge outward-g and also to prevent the bearings from springly from the trunnionstoward theends, as widely, ing apart. Through the helix It extends a so as may be desired for securely holding the loops screw I! which is threaded into the nut and has I of the wire from slipping off the ends of the its head l8 bearing against the outer'end of the trunnions. The intermittently moving blank helix. then passes under a punch which punches the The clamp is used in the manner common to central hole for the screw thread, and then such articles, being placed on the hose 8 with I6 v has several advantages.

the screw at least partly unscrewed. After the clamp is adjusted to proper position the screw is screwed up, thereby contracting the annular clamp body. As the diameter of the clamp con tracts, the wire bearing loops rotate slightly with respect to the trunnions, in a direction tending to wind up the bearing loops clockwise on the trunnions, as indicated by the arrow on Fig. 1, and the purpose in view is to permit free slip and so minimize such wind-up tendency.

As shown in Fig. 2, the wires Il diverge outward to the trunnions so' that they approach and engage the trunnions inside of the end flanges, and this divergence continues through the first half circle around the trunnions where all of the clamping stress is applied. Consequently, stress applied by the trunnions tends to draw loop bearings l3 away from the ends of the trunnions:

A preferred form of the trunnioned nut is clearly shown in Figs. 3, 4 and 5, and the method of making it is shown in Figs. 6 and 7. The cylindrical rod or wire :0 may be of diameter equal to the minimum diameter desired for the trunnions 15. The first pair of dies A, B, have similar equal projections C, which, as will be evident from Fig. 7, vertically flatten and laterally expand the rod, thus providing a flat with a bulging edge suitably shaped so that when severed at the center they form the wedgeshaped, loop-retaining projections Is, for the ends of adjacent trunnions of two blanks. The

same pair of dies also carry opposite similar circular projections D spaced apart from B a sufficient distance to leave an intervening cylindrical portion of the stock, suitable for the trunnions. These cylindrical projections D, D, punch-flatten the rod to form opposite cylindrical depressions 20 and also to bulge the metal laterally as at 22 to form a substantial strengthening annulus,

outside of said depressions.

Upon withdrawal of the dies, the thus formed unsevered blanks are fed forward to a piercing die E and punch F, whereby the hole for screwthread 2| is punched out, and on the next feed the blank is projected a proper distance beyond the shear G which severs the blank as indicated at the right in Fig. 6. The hole is then threaded. as at 2|, thereby'completing the nut, which may then be galvanized, or used without galvanizing.

The above feature of making the retaining member a wedge instead of an annular flange Asit can engage with the wire of loop l3 only at diametrically opposite points, it is easy to flatten the stock down to whatever thinness is necessary to spread the metal laterally and make the wedges 16a project radially to whatever extent may be considered necessary or desirable for safely holding the loops I3 from slipping off the ends .of the trunnion I5. I

While the wedge flattening at l6 might be in theplane of the axis of the nut and screw, and while a nut so made would be useful, it would require a die operating at a right angle to the always bear squarely on the cylindrical part l5; and in such case the wedge flattened part l6 will apply part or all of the tension stress to the first half turn of loop l3.

From the above, it will be evident that while the cylindrical part l5 may be made long enough and the wedge-edge l6 steep enough so that in practice the part l5 always has all the trunnion function and the wedge part l6 no trunnion function, I prefer the more practical proportions indicated in Fig. 3. With the trunnion and wedge proportions shown in this Fig. 3, it is evident that even with a tight fit for the loop 13 on the trunion I5, the wedge edge 16a. has some trunnion function; and if there is any looseness of fit of the loop on the trunnion, such as frequently occurs in practice and as clearly shown in Fig. 1, substantially all of the trunnion function may be shifted to the wedge l6. When screw, all of the stress would be applied on only one wedge edge "5a and this edge will have practically-single-point bearing on the loop and said hearing will be on a part of the loop where it will have maximum distorting. effect. Moreover, the thin wedge edge will tend to bite into the metal of the loop, and wind-up effect will be a maximum and will be in a direction to draw the bottom of the loop outward away from the hose. As contrasted with this, having the wedge flattened portion in a plane at right angles to the axis ofthe screw gives two opposite bearing points on each loop for the wedge edges I6a of each projection; and the wind-up effect indicated by the arrow on Fig. 1 is exerted mainly by the lower wedge edge lBa and so is exerted parallel with the surface of the hos instead of away from it. 7

As a concrete illustration of my invention, it may be noted that a two-inch hose clamp may be bent up from stiff resilient wire about inch in diameter, in which case the over-all length of my trunnion nut and its retaining wedges may be of an inch or less, the diameters, lengths and shapes of nut portions 20,,22,

cylindrical portions, l5, and wedge-flattened the drawing.

Of course all parts of the clamp may'be made on much smaller or larger scale; and their proportions may be varied and the trunnion nut may be used for purposes other than tensioning hose clamps.

While I have described my trunnioned nut as screw-threaded, it will'be obvious that most of my novel features of construction, functioning and method of making, will remain substantially the same, when screw I1 is is swivelled in the hole through the nut, and its thread engages a suitable thread in the other end of the clamp. Therefore, while nu as used in the appended claims may be ordinarily understood to imply a screw-threaded nut, it may also be construed to include a swivel nut, wherever necessary for equitable protection of novel features in claims that are patentable independently of whether the nut has swivel or thread engagement with the screw.

I claim:

1. A method of making screw-threaded nuts having integral oppositely extending trunnions including a substantially circular portion adjacent the nut and an end portion flattened and expanded to retain bearings from slipping off the approximately cylindrical stock having approxi ab a v nioned nut, the flattening including punch-flattening an area between the trunnions to expand' the metal to the diameter desired for the body of the nut to form a depression through the bottom of which a screw hole maybe formed; and on either side of said nut at intervals apl proximately equalling the desired lengthof the adjacent trunnions; and while flattened nut portion of a previously shaped,

blank, and finally circular portionof the trunnion, flattening the stock across the width thereof for alength equal to that of two end portions blanks and to a depth necessary to spread the metal laterally to a diameter substantially greater than that of said circular portionof the punching flattening the screw depression for one nut and a flat for the ends of twoa'djacent trunnions, punching a hole for a screw-thread through the punchsevering the blanks by'suces sive cuts-approximately midway of sa'id laterallyspread end portions.

2. A method of making screw-threaded nuts having integral oppositely extending trunnions including a substantially circular portion adja-, cent the nut and an end portion flattened and expanded to retain bearings from slipping on the end thereof, which method includes applying pressure in a single direction to flatten approxi- 'mately cylindrical stock having approximately the diameter of said rounded portions of thetrunnion,-said flattening being at intervals corresponding to the over-all length of the trunk nioned nut, the flattening including punch-flattening an area between the trunnions ,toexpand the metal to thediameter desired for the body of the nut to form a depression through the bottom of which a screw hole may be formed; and on either side of said, nut at intervals approximately equalling the desiredlength ofthe circu- I lar portion of the trunnion, flattening the stock across the width thereof for a length equal to that of two end portions of two adjacent blanks and to a depth necessaryto spread the metal laterally to a diameter substantially greater than that of said circular portion of the adjacent ,trunnions; and severing the blanks by successive cuts approximately midway of said laterally-spread end portions.

3. A method of making nut blanks having integral, oppositely extending projections each including a rounded portion of less diameter than the nut and a portion that is thinner than the rounded portion and has edges diverging toward the end, of the projection; which method includes feeding round stock having a diameter approximating that of said rounded portion, by feeding the stock, step-by-step, through distances corresponding to the over-all length of the blanks; and, equal to the length of one blank, punch-flatten ingthe stock to expand the metal to the desired diameter of the body of the nut and to form depressed portions through the bottom of which the screw-thread may be formed; flattening the stock to thin it and laterally bulge it over a length and to a depth required for diverging end portions of two adjacent blanks; and severing the blanks by successive cuts approximately midway of said laterally-bulged end portions.

4. A method of making nut, blanks having 01' two adjacent the body'of the nut between steps, at intervalsintegral, oppositely extending projections each including a rounded portion of less diameter than the nut; which method includes shaping 1 cylindrical stock having a diameter approximating that of said rounded portio'n, by feeding the stock step-by-step, through distances correspending to the over-all length of the blanks; and, between steps, at intervals equal to the length of one blank, puncheflattening the stock ing that of said rounded portion,

by feeding the stock step-by -step, through distances corre-" sponding to the over-all length of the blanks? and, between steps, at intervals equal to the lengthoi one blank, punch-flattening the stock to expand the metal to'the desired diameter of and to form depressed portionsthrough the bottom of which the screwthread may beformed; and, while thus punchflattening the screw depression for the nut of one blank, punchinga hole for a screw-thread through 'the punch-flattened nut portion of a 7 previously shaped blank and severing the blanks by successive cuts midway between the punch flattened depressions.

6. A method of making nut blanks having" integral oppositely extending projections each including a rounded portion of less diameter than the nut and an end portion that is thinner and wider than the rounded portion; which method includes shaping round stock having a cross sectional area, approximating the crosssection of the rounded portions of the projections, by feeding the stock step-by-step, through distances corresponding to theover-all lengths of the blank; and, between steps, applying single direction pressure to the stock to simultaneously flatten properly spaced portions thereof and shape the nuts and projections of a succession of integrally connected blanks; said flattening including punch-flattening the stock to expand the metal to the desired diameter of the body of the nut and to form depressed portions through the bottom of which the screw-thread may be formed; and simultaneously, at a suitable distance from the nut screw depression, flattening the stock to thin it and laterally bulge it over a length and to a depth required for the wider end portion of two adjacent blanks; and severing the blanks by successive cuts approximately midway of said laterally-bulged end portions.

7. A method of making nut blanks having integral, oppositely extending projections each including a rounded portion of less diameter than the nut and an end portion that is thinner and wider than the rounded portion; whichmethod includes shaping round stock having acrosssectional area approximating the cross-section of the rounded portions of the projections, by feeding the stock step-by-step, through distances corresponding to the over-all lengths of the flatten properly spaced portions thereof and shape the nuts and projections of.a"succession oi integrally connected blanks; said flattening including punch-flattening the stock to expand the metal to the desired diameter of the body of the nut and to .torm depressed portions through the bottom of which the screw-thread may be formed; and simultaneously, at a suit- I able distance from the nut screw depression, flattening the stock to thin it andlaterally bulge it over a length and to a depth required for. the wider end portion of two adjacent blanks; and,

while thus punch-flattening the screw depres-- sion for the nut of one blank and widening the stock to form adjacent ends for two blanks, punching a hole for a screw-thread through the punch flattened nut portion of a previously shaped blank; and severing the blanks by suc-' ing integral oppositely extending projections;

the nut portion having exteriorly rounded portions and a thinner depressed central portion through which the thread istapped; said rounded exterior portions curving longitudinally into substantially circular portions'adjacent the nut depression and the ends beyond said circular portions being flattened in a plane at right angles to the axis of the screw-thread and having laterally diverging edges of greater diameter than saidcircular portion.

10. A trunnioned nut the body of which is in planes transverse to the axis of the trunnionsv rounded and which merges longitudinally by smooth curves into trunnion portions of circular cross section, whereby adjacent portions of the nut body may be utilized for trunnion purposes.

'11. A nut formed with oppositely extending projections the end portions of which are laterally flattened to present edges diverging outwardly towards the end of each of the projections.

12. A nut formed with oppositely extending projections the end portions of which are laterally flattened and laterally widened in planes at right angles to the nut axis, to present edges diverging outwardly towards the end of each of the projections. Y

13. Ina hose clamp f a type in which the body portion includes two more or less parallel lengths of wire adapted to encircle the hose and a tensioning screw having conventional tangential relation to adjacent ends of said body portion and adapted to apply tension to the free ends of said wires through adjacent portions of said wires which are bent outwardly and helically inward to form a, pair of opposite upstanding single-turn bearing loops; a trunnioned nut in which said screw is rotatable, the trunnions of the nut each including a portion of circular cross-section adjacent the nut portion and an end portion which is flattened to spread the metal laterally so as to present wedge edges of greater radius than the circular portion, for

holding the loops against slipping off the end of the trunnion.

14. In a hose clamp of a type in which the' body portions includes two more or less parallel lengths of wire adapted to encircle the hose and a tensioning screw having conventional tangential relation to adjacent ends of said body portion and adapted to apply tension to the free ends of said wires through adjacent portions of said wires which are bent outwardly and helically inward to form a pair of opposite upstanding single-turn bearing loops; a trunnioned nut in which said screw is rotatable, the trunnions of the nut each including a portion of circular cross-section adjacent the nut portion and an end portion which is flattened to spread the metal laterally so as to present wedge edges of greater radius than the circular portion, for holding the loops against slipping off the end of the trunnion, the flattening and lateral spread of said end portions being in a plane approximately perpendicular to the axis of the screw.

JOHN J. MCLAUGHLIN. 

